Synthesis of Phthalimide

Combine fine powders of 70 g of phthalic anhydride with 23 g of urea, pour the mixture 1 L RBF, heat the mixture strongly. After 15-20 minutes the mixture turns into a foam then the reaction is complete. Cool down the mixture until it is warm and add 300 mL of hot water, break up the lumps. Pour the contents into a beaker, wash the RBF with 200 mL of hot water, stir the mixture well to break up all the lumps. Filter and wash twice with warm water. Dry the product at 150°C for 2h.